I know a lot of people are kind of dissapointed--Fitzgerald seems to have gone trolling rather than casting the wide net a lot of people were hoping--and i think this is not as good as a solid case against the whole White House, but i think Fitzgerald has a game plan in mind. My theory is pretty complex, so forgive the simplifications for here.
Fitzgerald's stated purpose is to investigate the now-infamous leak.
However, his indictment was of "Scooter" Libby and not on a leak charge but rather obstruction of justice.
During his press conference he said two things: that a grand jury was secret, but an indictment was public (reading between the lines--if my Fitzgerald Decoder Ring is up to the task--it seems like this is an important part to him and part of the investigation into the leak) and that the investigation was almost, but not quite, complete.
He didn't, that i caught, mention Rove, Cheney, or even say Novak's name. That, i think, is pretty huge.
I think he's missing something--we have seen him tease us with this stuff for a while now (he kept putting off the indictments, i mean)--and this looks like another move in his overall investigation and not the end result.
I think the comparison between fishing with nets and fishing with poles is fairly accurate, but Libby is the bait and not (as it might at first appear) the catch.
George W. Bush almost certainly knows--or could easily find out--what's really going on here by putting pressure on his staff, but he isn't doing that. Whether he's incompetent (which is certainly what he will claim--and incompetence is an impression he has been careful to give) or criminal the fact that the White House is still acting as though it has nothing to do with this ("No comment", indeed!) is damning.
The executive summary:
Bad: Fitzgerald doesn't feel he has a solid case against those who perpetrated the leak, at least not strong enough to indict at this time. He might, later, but we'll see.
Good: Fitzgerald seems to have a plan for extracting that information. A high-up is being charged on very serious grounds which do not let the rest of the administration off, either. (Remember he didn't get charged for the leak--he's not ultimately responsible, it seems--but rather for lying about the leak.)